Geographic Range

Capra nubiana, or the Nubian ibex, is the only ibex species adapted to life in hot, arid regions of the world. Capra nubiana was once widespread in the mountainous regions of northeastern Africa and the Middle East. Estimates of the full extent of this geographic range are based on ancient drawings and bone remnants. Presently, C. nubiana occurs in isolated populations in pockets of the coastal regions of northeastern Africa, the Sinai Peninsula, and the southeastern tip and western portion of the Arabian Peninsula. (Mendelssohn, 1990; Osborn and Osbornová, 1998; Shackleton, 1997)

Physical Description

Nubian ibex are one of the smallest ibex species and are sexually dimorphic. A female ibex is, on average, about one-third the size of a male. Males have an average weight of 62.5 kg, females average 26.5 kg. Shoulder height averages 75 cm in males and 65 cm in females. Total body length is 125 cm in males and 105 cm in females. (Gross, et al., 1995; Mendelssohn, 1990; Nowak, 1990)

The overall color of Capra nubiana individuals is a uniform tan (matching the surrounding rocky arid environs) with patches of black and white on the legs and a white underbelly. There is a color change that begins in August, where males become dark brown to black on their necks, chests, shoulders, sides of the belly, front side of the thighs, and upper forelegs. Males have long dark beards, which are used for scent marking and to excite the females during rutting. Older females also grow beards. (Gross, et al., 1995; Mendelssohn, 1990; Nowak, 1990)

Both males and females have horns, which are used for fighting, sexual selection, and territorial defense. A male’s horns are large, dark, and semi-circular, with annual rings on the back. The annuli grow twelve to twenty centimeters during the first five years of life, and then grow between two to four centimeters per year thereafter. Total length of the horns may reach 120 cm. The horns on an individual may have shorter annuli because of physical hardships during periods of drought or disease. The horn length in females reaches around 35 cm. (Gross, et al., 1995; Mendelssohn, 1990; Nowak, 1990)

Reproduction

During most of the year females and their young, as well as males under three years old remain in isolated herds of ten to twenty individuals. Adult males congregate in bachelor groups, displaying a marked system of dominance hierarchy. Males and females come together for the rutting season around October. The rutting season may continue into December. The mating system is polygynous, with only a few males siring many of the young. (Gross, et al., 1995; Kingdon, 1997; Nowak, 1990)

Throughout most of the year older males are solitary. They join females during the rut and try to drive off other males. Males will follow individual females and try to disrupt female herds. During the rut courting males seldom feed and expend much energy fighting or mating, resulting in severe deterioration of their physical condition. Both sexes exhibit crouching behaviors, tongue-flicking, and scent marking on the tail, beard and chest as part of their reproductive behavior. Reproductive success of male goats is directly correlated with body strength and horn size. Males often engage in forceful fights, whereby they crash against one another with their horns and try to overpower their opponents. Nubian ibex will erect the long dark hairs of the back while fighting.
Females typically mate two or three times during estrous, which typically lasts 24 hours. Males will often become excited during the rutting season, and spontaneous ejaculation has been reported, as well as masturbation via taking the penis tip in their mouths. (Kingdon, 1997; Mendelssohn, 1990; Schaller, 1977)

Gestation lasts 150 to 165 days, after which the young (usually one, but occasionally two) are born between May and June. Females reach sexual maturity at two years, and males at age three to six. For the first several days of their life, the kids are in hiding before joining their mother. (Gross, et al., 1995; Kingdon, 1997; Nowak, 1990)

Nubian ibex exhibit a high degree of parental investment in their offspring. Time to weaning averages two months. Over this period the females nurse their young daily and gradually teach them to forage independently and establish their position in the social hierarchy. Female ibex will only nurse their own offspring and are hostile to alien kids or females. This is presumably a result of the high reproductive effort that mothers invest in their offspring. (Kohlmann, et al., 1996; Muller, et al., 1995)

Most species of ungulates in mountainous regions depend on steep terrain to avoid predation. A grouping pattern unique to Nubian ibex among all other caprines has been observed in herds in the Avedat Canyon in Israel. Females leave their kids unattended in nursery groups in a steep-walled canyon with many other kids. The nursery is most likely an accidental trap that the kids have fallen into and cannot surmount the cliff walls to climb out. Mothers visit the nursery often to feed the kids, which stay in the nursery until they are mature enough to follow along on the steep cliffs. (Kohlmann, et al., 1996; Muller, et al., 1995)

Lifespan/Longevity

The oldest known individual of Capra nubiana lived 17 years in captivity. It is thought, however, that wild animals have much shorter life spans. Capra ibex, a related species, has been reported to live 10 to 16 years in the wild. (Jordan, 1969; Mendelssohn, 1990)

Behavior

Nubian ibex are most active in the twilight period, resting and ruminating occurs in the afternoon or at night. During the winter months, Nubian ibex will seek shelter such as rock outcroppings or caves to avoid the cold, wind, or rain. They often hollow out shallow depressions in the ground in which to rest. Along the shores of the Dead Sea and on the Arabian Peninsula, temperatures may exceed 38 degrees Celsius. During warm periods like these, Nubian ibex will often lie down or occasionally turn on their sides to stay cool. They often spend the hot periods of the day in shaded areas. (Kingdon, 1997; Mendelssohn, 1990)

Home Range

Most groups have ranges of only a few square kilometers, dominated by either females or males which will fight other encroaching members of the same sex. Males are the dispersing sex, and it has been shown that females within a group are highly related to one another. Groups are sexually separated in part due to the need to separate feeding areas for nutritional demands and to find water sources. (Gross, et al., 1995; Kingdon, 1997; Levy and Bernadsky, 1991)

Communication and Perception

Goats and ibexes are considered relatively non-vocal, but they have evolved a complex system of visual signals for aggression. Courtship displays are the most intensively studied component of communication in caprines, and are largely similar across all members of this groups. Males will display to other males with their horns, body movements, tongue or lips. They will also display to females. Females often bleat during estrus, and males may make several clicking, nasal sounds, or bleats. The rump patch is shown when animals are indicating submissiveness. (Fraser, 1986; Schaller, 1977)

During the rut, males will attempt to gain access to females by sniffing them, licking their anal areas, or nuzzling. If a female urinates, the male will then sniff her carefully, often curling his upper lip, which is a posture known as flehmen that further opens his olfactory senses. Non-receptive females will refrain from urinating, and simply continue grazing or occasionally run away. (Fraser, 1986; Schaller, 1977)

Horns are used for fighting, specifically for ramming rather than puncturing. Typically two males will spar, clashing their horns together to establish dominance. Occasionally females will also use their horns for aggression towards upstart young males or other females. Sparring between individuals seldom results in serious damage or bodily injury. (Fraser, 1986; Schaller, 1977)

Food Habits

Due to heat and water constraints, Nubian ibex usually feed during the night or twilight hours, and occasionally during the day. They descend to lower elevations to feed. The main diet includes herbs, shrubs, tree foliage (especially Acacia), buds, fruits, and occasionally grass. Nubian ibex especially prefer cadaba (Cadaba spp.) and camphorweed (Pluchea spp.). Nubian ibex forage in patches of high quality and where water is in close proximity. They drink water every day if available. (Hochman and Kotler, 2006; Kingdon, 1997)

Ecosystem Roles

Caprinae as a group is catholic in their diet, exhibiting a large range of foraging niches, with a generalized and adaptive diet. They often live in habitats with low primary productivity. Nubian ibex are expanding specialist feeders, meaning individuals forage selectively on plants of higher quality in large patches, and hence increase herbivory on all the plants in the patch.

Economic Importance for Humans: Positive

Nubian ibex have been hunted for meat and trophies, and even used as an offering during the Dynastic period in Egypt. Hunting is now illegal in most of the countries in which C. nubiana occurs. However, poaching is still widespread and protected areas are poorly enforced. Nubian ibex have been extirpated in Syria and Lebanon due to over-hunting. Ziswiller 1967 (as cited by Osborn 1998) lists several folk uses from nearly every part of the ibex for humans. Folk uses include the blood for gall stone easement, the heel bone for diseases of the spleen, feces for anemia, the heart for strength, and stomach fluids for many healthful properties. (Osborn and Osbornová, 1998; Shackleton, 1997)

Conservation Status

Capra nubiana is listed as an endangered species with an EN C2a classification on the IUCN Red List of Threatened Species. EN means endangered, and C2a means that the the population estimate is less than 2,500 mature individuals, with no subpopulations greater then 250 mature individuals and an overall declining population trend. Nubian ibex are not listed by the Convention on International Trade in Endangered Species (CITES) or the United States Fish and Wildlife Service (USFWS). Nubian ibex are protected in Israel, Jordan, and Oman. The population is thought to be at carrying capacity in Israel, but otherwise critically endangered in other areas. Threats to C. nubiana include habitat loss (via agriculture, livestock, and infrastructure development), hunting, pollution, and competition with non-native species. Protecting corridors which connect populations is particularly important for preventing population bottlenecks in this species. (Shackleton, 1997; Shkedy and Saltz, 2000)

Other Comments

Capra nubiana was first described by F. Cuvier in 1825 as a subspecies of Capra ibex, and synonyms for the species include C. arabica, C. beden, C. mengesi, and C. sinaitica. In 1987 C. nubiana was formally recognized as a distinct species.

In biomes with rich, lush habitats, caprines are typically replaced by cervids and larger bovids. In Africa, gazelles dominate the drier open steppes and grasslands. Thus Caprinae species have adapted to life in difficult environments. In a recent controversial study by Ropiquetet al. (2006), it was proposed that the common ancestor of wild goats arose from interspecific hybridization between ancestral goats (proto-Capra) and ancestral tahr (proto-Hemitragus). The product was a goat with a mitochondrial genome better adapted to high altitudes and with more efficient mitochondria, thus allowing them a special advantage to life in the mountains. (Grubb, 1993; Kingdon, 1982; Mendelssohn, 1990; Ropiquet and Hassanin, 2006; Uerpmann, 1987)

Despite their endangered status and elusive nature, Capra nubiana populations have become major tourist attractions in several areas. At the oasis of Engedi, on the Dead Sea, a certain subpopulation has become rather accustomed to humans, and males often predictably venture to a special watering hole popular with tourists. (Kingdon, 1982; Mendelssohn, 1990)

Contributors

Glossary

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

acoustic

uses sound to communicate

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

colonial

used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.

crepuscular

active at dawn and dusk

desert or dunes

in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.

dominance hierarchies

ranking system or pecking order among members of a long-term social group, where dominance status affects access to resources or mates

drug

a substance used for the diagnosis, cure, mitigation, treatment, or prevention of disease

ecotourism

humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

folivore

an animal that mainly eats leaves.

herbivore

An animal that eats mainly plants or parts of plants.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

motile

having the capacity to move from one place to another.

mountains

This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.

native range

the area in which the animal is naturally found, the region in which it is endemic.

pheromones

chemicals released into air or water that are detected by and responded to by other animals of the same species

polygynous

having more than one female as a mate at one time

scent marks

communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them

seasonal breeding

breeding is confined to a particular season

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

sexual ornamentation

one of the sexes (usually males) has special physical structures used in courting the other sex or fighting the same sex. For example: antlers, elongated tails, special spurs.

social

associates with others of its species; forms social groups.

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

visual

uses sight to communicate

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

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The Animal Diversity Web is an educational resource written largely by and for college students. ADW doesn't cover all species in the world, nor does it include all the latest scientific information about organisms we describe. Though we edit our accounts for accuracy, we cannot guarantee all information in those accounts. While ADW staff and contributors provide references to books and websites that we believe are reputable, we cannot necessarily endorse the contents of references beyond our control.

This material is based upon work supported by the
National Science Foundation
Grants DRL 0089283, DRL 0628151, DUE 0633095, DRL 0918590, and DUE 1122742. Additional support has come from the Marisla Foundation, UM College of Literature, Science, and the Arts, Museum of Zoology, and Information and Technology Services.